diff --git a/src/main.rs b/src/main.rs
index d352dcd..120c1a4 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -242,15 +242,17 @@ fn read_from_db2(id: u32) -> Option<Question> {
     let input = fs::File::open("test.bin").expect("open input");
     let mut input = std::io::BufReader::with_capacity(4 * 1024, input);
 
-    let mut len_data: [u8; LEN_SIZE] = [0; LEN_SIZE];
-    input.read_exact(&mut len_data).expect("read len");
-    let tab_len = LSize::from_le_bytes(len_data) as usize;
+    let mut first_data: [u8; LEN_SIZE] = [0; LEN_SIZE];
+    input.read_exact(&mut first_data).expect("read first");
+    let first_pos = LSize::from_le_bytes(first_data);
+    let tab_len = (first_pos as usize) / LEN_SIZE;
     let records_count = tab_len - 1;
 
     // println!(
-    //     "read tab_len done: {}, pos {}",
+    //     "read tab_len done: {}, pos {}, first_pos {}",
     //     tab_len,
-    //     input.stream_position().unwrap()
+    //     input.stream_position().unwrap(),
+    //     first_pos
     // );
 
     let index = match id {
@@ -264,29 +266,36 @@ fn read_from_db2(id: u32) -> Option<Question> {
     // println!("index {}", index);
     assert!(index < records_count);
 
-    let tab_tail_len = (tab_len - (index + 2)) * LEN_SIZE;
+    let data_pos = if 0 == index {
+        first_pos
+    } else {
+        let mut pos_curr_data: [u8; LEN_SIZE] = [0; LEN_SIZE];
+        input
+            .seek_relative(((index - 1) * LEN_SIZE).try_into().expect("index to i64"))
+            .expect("seek to tab pos");
+        input
+            .read_exact(&mut pos_curr_data)
+            .expect("read current pos");
+        LSize::from_le_bytes(pos_curr_data)
+    };
 
-    let mut pos_curr_data: [u8; LEN_SIZE] = [0; LEN_SIZE];
     let mut pos_next_data: [u8; LEN_SIZE] = [0; LEN_SIZE];
-    input
-        .seek_relative((index * LEN_SIZE).try_into().expect("index to i64"))
-        .expect("seek to tab pos");
-    input
-        .read_exact(&mut pos_curr_data)
-        .expect("read current pos");
     input.read_exact(&mut pos_next_data).expect("read next pos");
 
-    let data_pos = LSize::from_le_bytes(pos_curr_data);
     let data_pos_next = LSize::from_le_bytes(pos_next_data);
     let data_len = data_pos_next - data_pos;
 
-    // println!(
-    //     "pos {} | next {} | len {} | tab_tail_len {}",
-    //     data_pos, data_pos_next, data_len, tab_tail_len
-    // );
-    let data_pos = data_pos + tab_tail_len as LSize;
+    let tab_pos = input.stream_position().expect("stream pos") as u32;
 
-    input.seek_relative(data_pos as i64).expect("q seek");
+    // println!(
+    //     "pos {} | next {} | len {} | tab_pos {}",
+    //     data_pos, data_pos_next, data_len, tab_pos
+    // );
+    let advance_len = data_pos - tab_pos as LSize;
+
+    // println!("advance_len {}", advance_len);
+
+    input.seek_relative(advance_len as i64).expect("q seek");
     let reader = input.take(data_len as u64);
     let data = zstd::decode_all(reader).expect("zstd decode data");
 
@@ -344,12 +353,11 @@ fn db_writer2_task(rx: mpsc::Receiver<Question>) {
 
     buf.set_position(0);
 
-    let tab_data = vec![0u8; (table.len() + 1) * LEN_SIZE];
+    let tab_data = vec![0u8; table.len() * LEN_SIZE];
     let mut tab_cursor = Cursor::new(tab_data);
-    let len_data = (table.len() as LSize).to_le_bytes();
-    tab_cursor.write_all(&len_data).expect("write len");
+    let tab_size = (table.len() * LEN_SIZE) as LSize;
     for pos in table {
-        let pos_data = pos.to_le_bytes();
+        let pos_data = (pos + tab_size).to_le_bytes();
         tab_cursor.write_all(&pos_data).expect("write pos");
     }